The induction of tyrosine aminotransferase activity and its use as an indirect assay for endotoxin in mice infected with Plasmodium vinckei petteri

• Published in: International journal for parasitology Vol. 12; no. 4; pp. 279 - 284
• Main Authors: Gauci, Rebecca, Bennett, Donna, Clark, I.A., Bryant, C.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.1982
• Subjects: Animals; Cell-Free System; endotoxin; Endotoxins - analysis; Enzyme Induction; Enzymes, Host; Female; hepatic tyrosine aminotransferase; Liver - enzymology; malaria; Malaria - enzymology; Malaria - parasitology; Male; Mice; Mice, Inbred CBA; pathology; Pathology, Protozoa; Plasmodium - analysis; Plasmodium vinckei petteri; Plasmodium vinckei petteri (Protozoa); toxins; Tyrosine Transaminase - biosynthesis; pathology; Plasmodium vinckei petteri; hepatic tyrosine aminotransferase; malaria; mice; endotoxin
• ISSN: 0020-7519; 1879-0135
• DOI: 10.1016/0020-7519(82)90030-3

Gauci R., Bennett D., Clark I. A. and Bryant C. 1982. The induction of tyrosine aminotransferase activity and its use as an indirect assay for endotoxin in mice infected with Plasmodium vinckei petteri. International Journal for Parasitology 12: 279–284. It has been suggested that the malaria parasite contains an endotoxin-like substance which, by activating the reticuloendothelial system, causes much of the pathology of malaria when it is released into the host bloodstream during schizogony. In this study, an in vivo assay was developed, based on the determination of hepatic tyrosine aminotransferase activity in infected mice, to measure substances which act like endotoxin. Tyrosine aminotransferase is important in gluconeogenesis and is induced by endotoxin. Mice infected with Plasmodium vinckei petteri become sensitised to bacterial endotoxin as small amounts of endotoxin, without effect in uninfected mice, elevate tyrosine aminotransferase activity. The increase in sensitivity is gradual and progressive and is detectable by day 2 of the 9 day infection. Tyrosine aminotransferase activity is first lowered and then raised markedly during the course of the disease. A cell-free preparation of malaria parasites increased tyrosine aminotransferase activity when injected into mice sensitised with Coxiella antigen. These results are consistent with the hypothesis that parasitised red cells contain an endotoxin-like substance which directly or indirectly may be responsible for producing some of the symptoms of malaria in mice.